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  <section id="module-rlcompleter">
<span id="rlcompleter-completion-function-for-gnu-readline"></span><h1><a class="reference internal" href="#module-rlcompleter" title="rlcompleter: Python identifier completion, suitable for the GNU readline library."><code class="xref py py-mod docutils literal notranslate"><span class="pre">rlcompleter</span></code></a> — Completion function for GNU readline<a class="headerlink" href="#module-rlcompleter" title="Permalink to this headline">¶</a></h1>
<p><strong>Source code:</strong> <a class="reference external" href="https://github.com/python/cpython/tree/3.9/Lib/rlcompleter.py">Lib/rlcompleter.py</a></p>
<hr class="docutils" />
<p>The <a class="reference internal" href="#module-rlcompleter" title="rlcompleter: Python identifier completion, suitable for the GNU readline library."><code class="xref py py-mod docutils literal notranslate"><span class="pre">rlcompleter</span></code></a> module defines a completion function suitable for the
<a class="reference internal" href="readline.html#module-readline" title="readline: GNU readline support for Python. (Unix)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">readline</span></code></a> module by completing valid Python identifiers and keywords.</p>
<p>When this module is imported on a Unix platform with the <a class="reference internal" href="readline.html#module-readline" title="readline: GNU readline support for Python. (Unix)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">readline</span></code></a> module
available, an instance of the <code class="xref py py-class docutils literal notranslate"><span class="pre">Completer</span></code> class is automatically created
and its <code class="xref py py-meth docutils literal notranslate"><span class="pre">complete()</span></code> method is set as the <a class="reference internal" href="readline.html#module-readline" title="readline: GNU readline support for Python. (Unix)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">readline</span></code></a> completer.</p>
<p>Example:</p>
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">rlcompleter</span>
<span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">readline</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">readline</span><span class="o">.</span><span class="n">parse_and_bind</span><span class="p">(</span><span class="s2">&quot;tab: complete&quot;</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">readline</span><span class="o">.</span> <span class="o">&lt;</span><span class="n">TAB</span> <span class="n">PRESSED</span><span class="o">&gt;</span>
<span class="go">readline.__doc__          readline.get_line_buffer(  readline.read_init_file(</span>
<span class="go">readline.__file__         readline.insert_text(      readline.set_completer(</span>
<span class="go">readline.__name__         readline.parse_and_bind(</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">readline</span><span class="o">.</span>
</pre></div>
</div>
<p>The <a class="reference internal" href="#module-rlcompleter" title="rlcompleter: Python identifier completion, suitable for the GNU readline library."><code class="xref py py-mod docutils literal notranslate"><span class="pre">rlcompleter</span></code></a> module is designed for use with Python’s
<a class="reference internal" href="../tutorial/interpreter.html#tut-interactive"><span class="std std-ref">interactive mode</span></a>.  Unless Python is run with the
<a class="reference internal" href="../using/cmdline.html#id3"><code class="xref std std-option docutils literal notranslate"><span class="pre">-S</span></code></a> option, the module is automatically imported and configured
(see <a class="reference internal" href="site.html#rlcompleter-config"><span class="std std-ref">Readline configuration</span></a>).</p>
<p>On platforms without <a class="reference internal" href="readline.html#module-readline" title="readline: GNU readline support for Python. (Unix)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">readline</span></code></a>, the <code class="xref py py-class docutils literal notranslate"><span class="pre">Completer</span></code> class defined by
this module can still be used for custom purposes.</p>
<section id="completer-objects">
<span id="id1"></span><h2>Completer Objects<a class="headerlink" href="#completer-objects" title="Permalink to this headline">¶</a></h2>
<p>Completer objects have the following method:</p>
<dl class="method">
<dt id="rlcompleter.Completer.complete">
<code class="sig-prename descclassname">Completer.</code><code class="sig-name descname">complete</code><span class="sig-paren">(</span><em class="sig-param">text</em>, <em class="sig-param">state</em><span class="sig-paren">)</span><a class="headerlink" href="#rlcompleter.Completer.complete" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the <em>state</em>th completion for <em>text</em>.</p>
<p>If called for <em>text</em> that doesn’t include a period character (<code class="docutils literal notranslate"><span class="pre">'.'</span></code>), it will
complete from names currently defined in <a class="reference internal" href="__main__.html#module-__main__" title="__main__: The environment where the top-level script is run."><code class="xref py py-mod docutils literal notranslate"><span class="pre">__main__</span></code></a>, <a class="reference internal" href="builtins.html#module-builtins" title="builtins: The module that provides the built-in namespace."><code class="xref py py-mod docutils literal notranslate"><span class="pre">builtins</span></code></a> and
keywords (as defined by the <a class="reference internal" href="keyword.html#module-keyword" title="keyword: Test whether a string is a keyword in Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">keyword</span></code></a> module).</p>
<p>If called for a dotted name, it will try to evaluate anything without obvious
side-effects (functions will not be evaluated, but it can generate calls to
<a class="reference internal" href="../reference/datamodel.html#object.__getattr__" title="object.__getattr__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__getattr__()</span></code></a>) up to the last part, and find matches for the rest via the
<a class="reference internal" href="functions.html#dir" title="dir"><code class="xref py py-func docutils literal notranslate"><span class="pre">dir()</span></code></a> function.  Any exception raised during the evaluation of the
expression is caught, silenced and <a class="reference internal" href="constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate"><span class="pre">None</span></code></a> is returned.</p>
</dd></dl>

</section>
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<li><a class="reference internal" href="#"><code class="xref py py-mod docutils literal notranslate"><span class="pre">rlcompleter</span></code> — Completion function for GNU readline</a><ul>
<li><a class="reference internal" href="#completer-objects">Completer Objects</a></li>
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